formula

\[a^{3}+b^{3}+c^{3}-3abc=(a+b+c)(a^{2}+b^{2}+c^{2}-ab-bc-ca)\]

'Beauty is truth, truth beauty,'-that is all Ye know on earth, and all ye need to know.
John Keats,"Ode on a Grecian Urn"





















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